Clothes washing machine



July 10, 1962 s. v. HORECKY 3,043,125

CLOTHES WASHING MACHINE 4 Sheets-Sheet 1 Filed Feb. 29, 1960 FIG. 1-

INVENTOR. Stanley VHorec/ry BY A/W 4 Any July 10, 1962 s. v. HORECKY 3,043,125

CLOTHES WASHING MACHINE Filed Feb. 29, 1960 4 4 SheetsSheet 4 c! UPPER AGITATE UUTsT 0/ LUWER sP/W UUT 5T 02 LUWER T/WER M0T0R c3 UPPER AG/TATE M07. 5T a c3 LUWER sP/A/ MOI 5T E 04 UPPER AG/TATE UUT SI E 04 LUWER sP/W MUT RUW g E 06 UPPER RUvsE WATER a E 06 LOWER WA$R WATER c7 UPPER WATER TRAWsEER a g 07 LUWER MOTOR RELAY F/LL8 AGITATE sPUv E/LL Rl/vs 5R START WASH RIIIJZECENTOR.

Stanley VHorecky BY M A L/W United States Patent 3,043,125 CLOTHES WASHING MACHINE Stanley V. Horecky, Villa Park, 11]., assignor to General Electric Company, a corporation of New York Filed Feb. 29, 1960, Ser. No. 11,708 21 Claims. (CI. 68-12) This invention relates to Clothes washing machines of the time-cycle controlled type, and in particular, to means for interrupting the operation of the timing means at the start of a particular operation and for restarting the timing means upon the attainment of a predetermined operational condition.

Clothes washing machines of the domestic automatic type are under the control of a time-cycle mechanism which by way of a group of cams rotated at a predetermined rate to open or close switches in an established sequence, establishes various electric circuits to operate the machine in a predetermined cycle of operations which include, among other things, a washing operation, a centrifugal extraction operation to remove washing liquid from the clothes, a rinsing operation, and a centrifugal extraction operation to remove the rinse water from the clothes. In such washing machines, the washing and centrifugal extraction operations are carried out in a single tub or basket. In some vertical axis machines, the washing is eflected by oscillating the tub, and in others, by the oscillation or reciprocation of an agitator or impeller. Extractionis accomplished by rapidly spinning the tub, whereby the free water and that contained in the clothes passes over the top of the tub or through ports in the side of the tub. The extraction liquid is collected in a chamber from which it is usually removed by a pump operating continuously during the extraction cycle. In horizontal axis machines, the clothes are tumbled about in a detergent solution partially filling the tumbling drum, and extraction is accomplished by rapidly spinning the drum which ordinarily is perforated, thus permitting the liquid to escape through the openings in the wall of the drum. In this case also, the extracted water is caught in a collection chamber and is continuously pumped therefrom.

It is usually possible for the user to preselect the washing time according to whether the clothes load is heavy or light or more or less soiled. A load of heavily soiled work clothes, for example, may require as much as a ten minute washing operation; whereas light fabric, lightly soiled articles may be adequately washed in as little as three minutes. In spite of this wash time selection, the remaining operations of the machine are conducted pursuant to an inflexible schedule. It can take at least seven minutes, for example, to remove the desired amount of washing or rinsing liquid from a heavy load of clothes by centrifugal extraction; even longer to extract water from shag rugs and the like which have a very high water absorbency factor; and as little as three minutes for the centrifugal extraction of water from light clothes, particularly when they are made of synthetic fabrics. It will thus be seen that the inflexibility of the extraction operations pursuant to conventional practice has serious disadvantages. Articles may not be spun long enough to extract all of the water from very heavy articles and, of course, the extraction operation will be too long for the light synthetic fabric articles. The inadequate extraction time for the very heavy articles may result in a carryover of washing liquid into the subsequent rinsing cycle and may extract so little water at the end of the rinsing operation that the articles will literally be dripping wet when removed from the machine. With respect to the light synthetic articles, it is well known that abnormally long spinning times may set wrinkles in the fabric so securely that they are diflicult to remove even 3,043,125 Patented July 10, "1962 ice '2 by ironing. It is seen, therefore, that a centrifuging operation to attain a proper damp-dry condition is subjecLto many variables, and a fixed time period for the extraction operation can be only a compromise, at best.

It is, therefore, an object of the invention to provide a control circuit for washing: machines of the automatic time-cycle type in which means responsive to the large volume of water extracted at the commencement of a centrifuging operation will inactivate the time-cycle switch until there is a very substantial reduction in the amount of water being extracted, whereupon the time-cycle switch will resume operation to continue the centrifuging step for a short, fixed period.

It is another object of the invention to provide an automatic control of the extraction cycles of an automatic washing machine, pursuant to which the washing machine operates more efficiently to extract liquid from the clothes.

In practicing the invention, I rely upon the circumstance that during the very first stages of operation of a washing machine during a centrifuging cycle, large volumes of free liquid in the tub are thrown out of the tub and into a collection chamber surrounding the tub, long before the tub reaches the final centrifuging speed. For example, it has been found that in the average size vertical axis washing machine in which the tub contains about sixteen gallons of water, a very large portion of this water leaves the tub and gathers in the collection chamber within about twenty-five seconds after the tub begins to rotate. In this time, the tub may have come to only about r.p.m. whereas the final extraction speed may be as high as 550 r.p.m.; nevertheless, the free water within the tub has been removed from the tub and the remaining extraction operation is intended to remove the water from the fabrics themselves. Domestic washing machines ordinarily extract to the degree that at the end of the extraction operation, the moisture content of the clothes is about 100% of the weight of the clothes. For example, considering an eight pound clothes load, the centrifuging operation will extract all but about eight pounds of water from the clothes. Additional spinning, except at very high speeds, is not productive of a substantial further reduction in the amount of water remaining in the clothes. It has previously been noted that during an extraction operation, a discharge pump is continuously operating. These discharge pumps are small, having a pumping capacity of about five gallons per minute, and are, therefore, incapable of handling the flood of water leaving the tub at the commencement of the spinning operation. The water, therefore, accumulates in the collection chamber.

A presently preferred embodiment of my invention utilizes a pressure-responsive switch to terminate the filling of the tub and initiate the washing operation. The fill valve remains open until overflow from the tub into the collection chamber has submerged the switch in about two inches of water, whereupon the switch operates to terminate the water filling operation and establish an electric circuit which energizes the main drive motor to initiate the washing operation. I have adapted this pressure-responsive switch to carry out the objects of my invention, by adding an electric circuit which interrupts the timer-motor circuit after centrifugal extraction has continued for a time suflicient to submerge the switch in slightly more than two inches of water. This will be very shortly after an extraction cycle begins. Because the pressure switch interrupts the circuit for the timer motor, the cam-controlled switches remain as they were at the commencement of the operational cycle. One of these switches, of course, had been closed to initiate the centrifuging operation and it is apparent, therefore, that so long as sufiicient water is leaving the tub to retain the pressure switch in its timer-motor disabling position, the centrifuging Operation will continue, and the discharge pump will continue to operate, Sooner or later, depending upon the type of fabric and the clothes load in the washing machine, the pumping rate; of the discharge pump will exceed the rate at which water is entering the collection chamber and the level of water in the chamber will recede until it is below that necessary to maintain the switch in its said position. The control circuit thereupon operatesito reinstate the operation of the timer motor. To insure the continuance of the centrifuging operation for anadditional time calculated to etfect the complete removal of water from the clothes, the time switch maintains the spin operational condition for an additional predetermined period which may be two minutes, whereupon the washing machine proceeds to its next operation or terminates its operation according to whether the centrifuging was for the removal of wash water or rinse water from the fabrics.

In other embodiments of the invention presently described, I employ apair of probes or spaced electrodes in the path of escape of water from the tub.," Water impinging upon said probes completes a circuit thereacross and by suitable means I translate this circuit operation into control over the timer motor. In still another embodiment, I catch the water as it escapes from the tub and utilize the weight of the water to overbalance a tilting switch operator which controls the timer motor, as aforesaid.

Other features and advantages will be apparent from the following detailed description of three embodiments of the invention, read in connection with the accompanying drawings in which:

FIG. 1 is a side sectional elevation of a clothes washing machine embodying one form of the present invention;

FIG. 2 is a circuit diagram of the control system employed in the FIG. 1 embodiment;

FIG. 3 is a fragmentary sectional elevation of a washing machine illustrating a second embodiment of the timer control actuator;

FIG. 4 is an elevational view of the device of FIG. 3, looking in the direction of the arrows 44 of FIG. 3;

FIG. 5 is a circuit diagram for the control system of the FIG. 3 embodiment;

FIG. 6 is a fragmentary side sectional elevation of a third embodiment of the time control actuator;

FIG. 7 is a schematic circuit diagram for the FIG. 6 embodiment;

FIG. 8 is a sectional elevation of the water pressure switch actuator, looking in the direction of the arrows 8-8 of FIG. 1;

FIG. 9 is. a sectional elevation of the switch element of FIG. 8, looking in the direction of the arrows 99 of FIG. 8; and

FIG. 10 is a cycle timing diagram for the control circuits of the present invention.

A typical automatic washing machine with which the present invention is very advantageous comprises, as shown in FIG. 1, an outer casing 1 having a water-tight bulkhead 2 which divides the casing into a water collection chamber 3, and a machinery compartment 4. Suitably supported within the machinery compartment, as by the supporting structure 5 are a main drive motor 6, a. transmission 7, and a pump 8. The inlet 10 to the pump communicates with an inlet fitting (not shown) in the bulkhead 2 and the discharge hose 11 is arranged to con-. duct effiuent to a suitable discharge point, such as the usual laundry tub (not shown).

A washing tub 12 isdisposed within the water collection chamber 3. A bladed agitator 14 is disposed within said tub. Said agitator is fixed to the end of an agitator shaft 15 which is connected to the transmission 7 for, oscillation thereby during operation of the motor 6 in one direction of operation, as is well known in the art. The tub itself is mounted on a tubular shaft 16 which also communicatesv with the transmission 7 and is arranged to be rotated thereby during rotation of the motor in the opposite direction, also as well known in the art. The transmission, the exact drive mechanism, and the means for rotatably supporting the tub may be in all respects conventional and details thereof have been omitted for brevity, for they form no part of the present invention.

It will be noted that the tub 12 is upwardly and outwardly flared and that at substantially the maximum diameter it has a plurality of water ejection holes 17 arranged in a single row. The tub has a heavy balance ring 18 secured to its upper rim to help stabilize the tub during the rapid rotation thereof in an extraction cycle.

The upper part of the housing is enclosed by the cover structure 19 which is provided with a raisable lid 20 afiording access to the tub by way of the depending rubber sleeve 21 which serves to prevent small articles of clothing from. being carried over the top of the tub during a washing or centrifuging operation. Said sleeve 21 may be arranged pursuant to US. Patent 2,703,974 granted on March 15, 1955 to Kendall Clark for flexible guard sleeve, etc., and assigned to my present assignee. The rear portion of the cover structure 19' provides a space for the accommodation of a conventional solenoidcontrolled water valve 22 having inlets 23 and 23.1 arranged respectively to be connected to the hot and the cold water supply piping (not shown). The valve has an outlet 24 to which is attached a fitting 25 and outflow terminal 26 which discharges water against the outer wall of sleeve 21, whence it flows into the tub 12, as fully explained in the Clark patent. A backsplash member 27, mounted on the top structure, houses a conventional time-cycle controller 28 having a setting knob 29 mounted on the front of the backsplasher for ready accessibility.

A pressure sensitive switch 30 is mounted in the bulkhead 2. Said switch, as shown in FIGS. 1 and 8, has a mounting 31 which supports a flexible rubber diaphragm 32 within the collection chamber 3, and a switch housing 33 disposed externally of the chamber 3. A plunger 34 (FIG. 8) having a large diameter head 35 in engagement with the underside of the diaphragm 32 cooperates with the pivotally mounted lever 36 and the switch actuator 37 to operate the single pole, double throw switch within the housing. The switch blade 38 is biased by the leaf spring 38.1 and the illustrated overthrow mechanism to close against a lower contact 39 when there is less than two inches of water depth in the collection chamber. When there is more than this depth, the downward movement of plunger 34 causes lever 35 to move away from actuator 39, whereupon the overthrow mechanism will cause the switch blade 38 to close with the upper contact 40. An adjustment spring 41 is available to adjust the bias of the operating plunger. In the present embodiment of the invention, the pressure switch 30 controls the operation of the time-cycle controller-28 during the centrifuging operations, as later explained. Further, by way of preliminary explanation, it is noted that the main drive belt 42, by means of which the transmission is driven by the motor 6, also engages, the pump drive pulley 43, whereby the pump is in operation whenever the motor 6 is operating. The pump 8 is of a well-known bi-directional type and operates at full pumping efiiciency regardless of the direction of operation of the motor. In a washing machine presently manufactured by applicants assignee herein, the pump has a pumping capacity of the order of five gallons per minute.

In using a washing machine of this type, the clothes are placed within the tub, detergent is added, and then operation of the time-cycle switch is initiated by rotating or otherwise manipulating the control knob 29 to an "on position which, as later explained, starts the timer motor and energizes the solenoid operated valve to admit water into the tub by way of the fitting 26. In passing, it should be noted that the washing machine of the type illustrated has both hot and cold water solenoids and selection devices whereby the'user may select the temperature of the water to be used for the washing and rinsing operations. For simplification of the present description of operation, it will be assumed that the user has elected to wash and rinse with hot water only; and the circuit diagrams herein show only a hot water valve solenoid. The filling proseeds until water overflows into the water collection chamber through/the ports 17 and continues to flow until there is a two inch depth in the chamber, whereupon the resulting head of water on the diaphragm of the pressure switch operates the switch to open "the solenoid valve circuit and to close the drive motor circuit. The motor operates in a direction driving the transmission 7 in the agitation cycle, whereupon the transmission oscillates the shaft on which the agitator is mounted. The pump is operating at this time, also, and because there is no more water entering the chamber 3 (except for that which splashes through the opening 17) the chamber is evacuated of water. The washing operation proceeds for the predetermined time following which the timer halts the motor and reverses it to cause the motor -to spin the tub. Because of the load of water and clothes, there will be as much as eighteen gallons of water and eight pounds of clothes in the tub, and further because the motor is usually connected to the transmission by a centrifugal type clutch, the tub 12 picks up speed gradually. In a matter of seconds, however, the tub will be rotating at from 80 to 100 r.-p.m. which produces suflicient centrifugal forces to cause the free water in the tub to spill through the holes 17 in amounts much greater than the pump can handle, whereupon in from twenty-five to thirty seconds following the commencement of the spin operation,,water will have accumulated in the bulkhead almost to the bottom of the spinning tub and the head of water actuates the pressure switch to break its lower contact and make its upper contact. As presently explained, this action interrupts the timer circuit halting the usual stepby-step advance of the timer cams, but maintains the drive motor 6 in operation. The tub continues to spin and, depending upon the nature of. the clothes load, its water absorbency, etc., the pump shortly becomes increasingly able to handle the volume of water being extracted and commences to reduce the level of water in the tub to below that which is necessary to sustain the open circuit condition of the timer motor, and the timer againbegins operation. At this time, there is probably only a light spray issuing through the port 17. The timer continues the centrifugal extraction operation for an additional fixed duration; for example, two minutes, whereupon the timer re-establishes the control circuit for the next operation which is usually that of again filling the tub to overflow for an agitated rinse operation. The remaining washing machine operations are substantial repetitions of the above, terminating in a final rinse and a final rinse water spinout. It will thus be seen that the interruption of the timer circuit followed by the brief additional centrifugal extraction operation not only insures removal of water from the clothes within the limits of the centrifuging speed, but insures a complete emptying of the water collection chamber.

The circuit diagram of FIG. 2 illustrates the control circuitry necessary for the cycle of operation of a machine utilizing the preferred embodiment. In this figure, the time cycle controller switch 28 is shown provided with a synchronous timer motor 28.1 which through generally known transmission mechanisms (not shown) rotates an output cam shaft 28.2 in a step-by-step manner at the 7 rate of 6 each minute. Byfl'the use of the transmission mechanism the cam shaft, 28.2 in addition to its rotational direction may be displaced axially by manually pushing or pulling on the timer knob 29 by means of which the user operates the timer to start the operation of the washing machine and preselects the duration of the washing operation. The cam shaft shown carries six cams, C1, C2, C3, C4, C6 and C7. Cam C1 is a three level cam with an armature spring or contactor 50 which can be closed to its upper stationary spring contact 51, to its lower contact 52, or may assume an intermediate open position. Cam C2 is a two level cam with an armature spring contact 53 which may open or close relative to lower stationary contact 54. Cam C3 is also a three level cam with its contact armature 55 movable between upper contact 56 and lower contact 57 from an intermediate open position. Cam C4 is also a three level cam with a contact armature 58 capable of being closed to upper contact 59, lower contact 60, or intermediately open therebetween. Cam C7 is a three level cam with a contact armature 61 which may be closed to upper contact 62, to lower contact 63 or may assume an intermediate open position. The last of these cams C6 is also a three level cam with its contact armature 64 which may be closed to either the lower contact 65, the uper contact 66, or intermediately open.

The time cycle control further includes a line switch 67 which responds to the depression of the external knob 29 in a downward direction with respect to FIG. 2. This depression and the consequent axial movement of shaft 28.2 closes the line switch armature contact 68 to stationary contact 69 and the switch remains closed throughout the operational cycle.

More specifically, the operation of the control circuit of FIG. 2 when viewed in conjunction with the cam closure diagram FIG. 10 is as follows: the manual control knob 29, as mentioned, is depressed axially to close line switch 67 and further is rotated to the rotary start position. When the cam shaft is in the start position, cam C2 closes its contact armature 53 to the lower stationary contact 54. This closure completes a circuit to the timer motor 28.1. The circuit to timer motor 28.1 may be traced from a conventional source of 60 cycle, single phase, alternating current (not shown) through lead conductor L2, contacts 68, 69, 54, 53, lower contact 39 of the pressure switch, switch blade 38, and the timer motor 28.1 to conductor lead L1 of the current source.

The timer motor then proceeds to rotate cam shaft 28.2 for a time controlled start period, at the conclusion of which cams C1, C3 and C4 close their contact armature to the upper stationary contacts and cams C6 and C7 close their armatures to their lower contacts, and cam C2 returns to open circuit position, as indicated in FIG. 10. This multiple cam operation serves to initiate the wash fill period. The previously described original circuit path to the timer motor is opened by the restoration of cam C2. Cams C6 and C7 on closure complete an operating path to the water solenoid 22.1. This operating path may be traced from the current source and conductor lead L1 through solenoid 22.1, contacts 65, 64, motor centrifugal switch contacts M3, M2, contacts 40, 63, 61, 69 and 68 to conductor lead L2 and the current source. Solenoid 22.1 is thereby energized and introduces water into the tub through the water inlet fittings. The water introduced fills the tub 12 to the level of the water ejection holes 17, at which time the water overflows into the collection chamber 3. The water level in the collection chamber continues to rise until the predetermined level which we have set as 2" is reached. At this level diaphram 32 is depressed causing the pressure switch 30 to move its switch blade 38 from contact 39 to contact 40. This movement in turn closes circuits to the main drive motor and the timer motor. The main drive motor is started by the simultaneous energization of its start winding and its run winding. The energization path for the motor start winding may be traced from the power source and conductor lead L1 through contacts 56, 55, motor terminal M82, motor start winding MS, terminal MSl, motor start winding centrifugal switch contacts 70 and 71,

7 contacts50, 51, 58, 59, 38, 40, 63, 61, 69 and 68 to conductor lead L2 and the power source. The circuit to the motor run winding extends from the current source and conductor lead L1, through motor run terminal MR2, motor run winding MR, motor terminal MR1, contacts 58, 59, 38, 40, 63, 61, 69, 68 and conductor lead L2 back to the power source. The motor then begins its rotation in the clockwise direction for agitation. As mentioned also, the timer motor 28.1 is operated over a path which will be called herein the alternate operate path and which may -be traced as follows: current source lead L1, timer motor 28.1, contact blade 38, contacts 40, 63, 61, 69, 68 and conductor lead L2 back to the power source. The timer motor thereby rotates its cam shaft 28.2 at the preset rate timing the agitate period.

At this time, the motor has been started in its agitate direction and thereafter accelerates under the control of both its windings until its synchonous speed is approached. As this speed is being approached, the start winding centrifugal switch operates. This centrifugal switch may be of the generally known fly-ball governed type which actuates its contacts when the motor has accelerated to a predetermined level. The actuation of the switch causes armature contact 70 to break away from contact 71 opening the motor start circuit. The motor start winding is thus de-energized and the motor continues to rotate under the control of its run winding, and the motor by way of transmission 7 agitates the agitator in the known fashion.

A second armature contact M2 is also actuated by the acceleration of the main drive motor and on actuation breaks its previously closed path to M3, opening the water solenoid energizing circuit. Armature M2 then closes a circuit to stationary contact M1 which in effect shorts out the pressure switch 30. By this circuit closure, the timer motor is locked operated for the duration of the main drive motor agitation period. This lock path is necessary since the liquid in the collection chamber may be expelled sufficiently, during the agitate cycle to allow switch 30 to restore, thus closing armature 38 to contact 39 opening the circuit which has been described as the timer motor alternate operate path. This locking path extends from conductor L2 through closed contacts 68 and 69, closed contacts 61 and 63 of cam C7, contact 40, and closed contacts M2 and M1 to the timer motor 28.1 and lead L1.

During the agitate cycle, the time cycle controller 28 has continued its rotation of cam shaft 28.2 and, at the conclusion of the timed agitate period, cam C2 recloses its contact pair of cams C3, C4, and C6 open their previously closed contacts de-energizing the main drive motor 6. In view of the fact that armature M2 breaks with contact M1 and recloses with contact M3, and the pressure switch contacts 38 and 39 are closed, timer motor 28.1 operates by way of the closed circuit at cam C2 as previously described.

At this time the tub is full of water which must be removed from the machine prior to the beginning of the rinse cycle. In order to accomplish this extraction removal, the main drive motor must be closed in its spin or centrifuging direction. To thus energize the motor, the timer-operated cams C1, C3, C4, and C7 close their armature contacts to their lower stationary contacts. These closures complete paths to both the drive motor start and run windings. The motor start path may be traced from the power source and conductor lead L1 through contacts 52, 50, 71, 70, terminal MSl, motor start winding MS, terminal MS2, contacts 55, 57, 58, 60, 69, 68 and conductor L2. It should be noted that the direction of energization of the start winding is opposite the direction which was employed for energizing the start winding during the agitation cycle. This opposite direction of energization will allow the motor to rotate in the counterclockwise direction necessary for the centrifuging operation. The motor run winding is energized over a path from the power source conductor lead L1 through terminal MR2, drive motor run winding MR, terminal MR1, contacts 58, 60, 69, and 68 to conductor lead L2 and the power source. The motor begins to accelerate in its .spin direction and after the motor has approached its synchronous speed, centrifugally actuated contacts 70 and 71 open the circuit to the start winding and centrifugal armature contactor M2 closes to stationary contact M1. Shortly thereafter, cam C7 restores opening the alternate operate path to the timer motor during the remainder of the extraction period.

The drive motor 6 continues to accelerate to its running speed, thereby rotating wash tub 12 and pump 8. Wash tub 12 approaches its centrifuging speed at which time water is ejected from the tub through the water ejection holes 17. This water ejection begins at a high flow rate due to the large amount of free water in the tub. This flow rate initially is considerably' greater than the pump capacity and as a result the ejected water accumulates in the water collection chamber until the accumulation reaches the 2" level. When this level is reached, the pressure switch actuates its contact blade 38 against stationary contact 40. This actuation opens the original path and at this time the alternate path through cam C7 is not available. The timer motor operate path to timer motor 28.1 is thereby de-energized, suspending the control of the timer over the duration of the extraction cycle. The cycle length is thereaftergoverned by the action of the pressure switch 30. Thus, as long as 2" of water remain in the collection chamber above the pressure switch, the timer remains inactive. During this period, cam C6 may close its armature to its upper contact 66 for a short period to provide a flow of clean water into the tub to flush out any sediment or lint. This added water is also ejected and does not substantially increase the cycle length.

Throughout this spin period, the pump 8 has been expelling the wash water from the outer collection chamber at its maximum rate. As described previously, this maximum pumping rate is not sufficient to reduce the water level in the collection chamber as long as the water is being extracted from the tub at a high rate. However, as the level of free water in the tub decreases, the amount of water being extracted from the tub also decreases. The pump then can begin to expel water stored in the chamber and consequently the pump action begins to decrease the water level in the collection chamber. As the water level in the chamber decreases below the '2" level necessary to keep open the contacts 38 and 40 of switch 30, the switch returns to its normal position closing blade contact 38 to contact 39. This closure completes the original operate path to thetimer motor which then resumes its timed rotational control of the cycle length. The control timer 28 continues its timed control.

of the spin extraction .for a fixed time period with no changes in cam closure. This time period which may be of one, two or three minutes duration is preset by the cam design and must be chosen to allow sufiicient time for the pump to dispose of the remaining water in the collection chamber. At the conclusion of this timed extraction period, which we have assumed to be two minutes, cams C1, C3 and C4 all restore to their intermediate position de-energizing the main drive motor 6. The circuit to the timer motor remains closed and the timer continues its time control functioning.

After the final timed portion of the spin cvcle, cams C6 and C7 close their armature contacts to their upper contacts to start the rinse fill period. This dual closure completes an energizing path for the water solenoid as follows: line conductor L1, water solenoid 22.1. contacts 66, 64, 62, 61, 69, 68 and line conductor L2. Energization of the solenoid causes water to flow into the tub as in the prior cycle. After a timed rinse fill period somewhat shorter than that required to completely fill the tub, cams C1, C3 and C4 close their armature contacts to their upper stationary contacts to prepare the main drive motor circuits in the agitate direction over the previously described agitate paths. Cam C7 switches its armature from its upper to its lower contact to close a preparatory circuit for the main drive motor operation and further to place the water solenoid 22.1 under the control of pressure switch 30. Also, at this time, cam C2 restores to its open position opening the original operate path to the timer motor 28.1. The water solenoid remains energized causing water to flow into the tub as in the previously described fill operation. The tub then overflows into the collection chamber and finally the switch 30 is actuated to reoperate the timer motor over the previously described path to continue the timed cycling. The main drive motor 6 is also energized in its agitate direction over the previously described paths and on acceleration opens the water fill solenoid circuit at contacts M2.M3. The drive motor proceeds to oscillate the agitator through the rinse cycle.

When the timer has rotated to the position indicating the termination of the rinse agitation period cam C2 reoperates, reclosing its armature 53 to stationary contact 54 closing the original timer operate path. At this time cams C1, C3 and C4 restore their armature contacts to the open position prior to the initiating of rinse extraction. Cams C1, C3 and C4 thereafter close thei armature contacts to their respective lower stationary contacts and cam C7 retains its armature closed to its lower contact to energize the motor start and run windings to start the counterclockwise rotation of the motor and consequent spin of the basket. As in the previous extraction operation, the basket begins its rotation and water is extracted from the clothes and the wash tub until a sufficient pressure is built up in the collection chamber to cause switch 30 to open the timer motor original operate path. Shortly thereafter cam C7 returns to its intermediate open position opening the alternate operate path to the timer motor. The spin cycle therefore continues without timed control until less than two inches of water remain in the collection chamber at which time pressure switch 30 closes its armature 38 to contact 39 reclosing the motor timer operate path. Timer motor 28.1 continues to rotate for the predetermined time period of two minutes at which time substantially all of the extracted water has been removed from the collection chamber and the extraction period is completed.

The second method of controlling the length of the spin extraction periods is by the use of spaced electrodes, the details of which are shown in FIGS. 3 and 4 and the circuit of which is shown in FIG. 5. In FIG. 4 there is shown the two electrodes 80 and 81 which are positioned in spaced-apart relation by the insulating ring 82. The spacing between these electrodes is such that an electric circuit will be completed by water discharge from the tub during that portion of the extraction cycle in which a substantial amount of water is leaving the tub. To achieve this end, the insulating ring is mounted to the machine outer casing 1 in the area outwardly adjacent the water ejection holes 17. A suitable mounting bracket 83 is used to secure the ring to the casing. This mounting location insures that these electrodes, by virtue of their being in the path of liquid being extracted from the tub will be contacted by this liquid flow. A secondary source of liquid spray to the electrodes is furnished by a bleeder tube 85. This tube is fed by pump 8 in such a manner that as long as water is being expelled by the pump in substantial .quantity, the bleeder tube will receive a small portion of this liquid in the form of a spray and will cause this liquid spray to impinge on electrodes 80 and 81, thereby completing a circuit across the air gap between these electrodes. 1

The circuitry necessary for this electrode embodiment is shown in detail in FIG. 5. The circuit of FIG. 5 is identical in the main to that of FIG. 2 except that in FIG. 5 there is employed a conventional single pole pressure switch 30' which includes an armature contactpr 38 and a stationary contactor 39'. Switch 30' is used only for the fill control operation in the manner previously described for the prior embodiment. The duration of the extraction cycle in this second embodiment is controlled by the electronic signal amplification circuit designated 100. This electronic circuit includes a cold cathode tube 101 with its cathode 103, grid 104 and anode 105. An electro-magnetic relay 106 is positioned across the tube output circuit. The electro-magnetic relay 106 has an armature contact R1 and stationary contact R2 to provide a normally closed operating path from armature 53 of timer cam C2 to the timer motor. The electronic circuit further includes a grid bias resistor 107 which is electrically positioned between electrode 80 and the grid 104. A second bias resistor 108 is also provided and appears in the form of a potentiometer, the slider of which is located in the electrical circuit from the electrode 81 to the cathode 103. To guard against the false releasing of the relay due to the possible intermittent striking of the electrodes by the water ejected, a capacitor 109 is connected'across the relay terminals. The capacitor will make the relay action a little more sluggish resulting in a slow acting relay which will hold operated for short periods of an open circuit at the electrode gap.

The operation of the circuit of FIG. 5 is identical to that of FIG. 2 except during the spin cycle. At the start of the spin cycle the wash tub is completely full of wash liquid, which of course includes wash water, whatever additives have been placed into the water, and entrained dirt removed from the clothes. As the spin cycle begins, cams C1, C2, C3, C4 and C7 all have closed their armature contacts to their respective lower stationary contacts. Both the motor start and motor run windings are energized over the previously described paths for the spin cycle. As described previously, the motor accelerates in the spin direction and the start winding is later deenergized when the drive motor approaches its running speed. The run winding continues to accelerate and accelerates the tub to its centrifuging speed. The drive motor also operates the liquid expelling pump 8 to remove accumulated water from the collection chamber.

cuits for the timer motor 2.8.1: from L1 through motor 28.1, through the connection point at pressure switch contact 38', centrifugal switch contacts M1 and M2, closed contacts 63 and 61 of cam C7, closed contacts 68, 69, and to L2; and from L1 through motor 28.1, the closed contacts R2, R1 of relay 106, closed contacts 53, 54 of cam C2, and closed contacts 68, 69 to L2. Shortly after the" spin cycle begins, cam C7 contact 61 restores to its intermediate position, breaking the first of the timer operating circuits. Cam C2 remains closed on its contact 54. As the tub approaches its centrifuging speed, liquid is ejected from the tub through the water ejection holes in an increasing amount. As this amount of ejected liquid continues to increase, a portion of the ejected liquid floods electrodes 80 and 81 in the manner shown in FIG. 3 and tends to complete the circuit across the air gap. It has been found that the time required for the liquid to short this contact gap may be on the order of seven seconds after the tub reaches centrifuging speed. When the electrodes are shorted by the spray, a signal is impressed on the input circuit of cold cathode tube causing the tube to fire in the generally known manner. Firing of the tube completes the output circuit to the electromagnetic relay 106. The relay operating path may be traced from conductor lead L1 through the winding of relay 106 and anode to cathode 103 and conductor lead L2. On operation of relay 106, its armature R1 is drawn away from stationary contact R2 breaking the circuit to the timer motor. The drive motor operating circuit is not disturbed by the operation of relay 106 and the drive motor continues to centrifuge the tub and to the spray from the liquid ejecting holes, which has been striking the electrodes, a second spray from tube 85 has also been striking the electrodes. Tube 85, as mentioned, acts as a bleeder from the pump and transmits a spray to the electrodes as long as an appreciable flow of liquid is being expelled by the pump. Thus, the electrodes remain shorted sufliciently to keep the slow acting relay operated as long as a substantial flow of liquid is being extracted from the tub and/or substantial flow is being processed by the pump. As a result of the combined effects of these sprays, relay 106 remains operated until flow of liquid from the tub to the collection chamber, and the flow of liquid being handled by the pump, is too small to complete the circuit across the electrodes 80 and 81. At this time the contact gap across electrodes 80 and 81 opens. Opening of this shorted path in the input circuit to the tube causes the tube to stop conducting, which in turn de-energizes relay 106. The relay restores and recloses its armature R1 to stationary contact R2. Closure of this contact pair recloses the timer motor circuit and the timer motor again operates over the previously described path. Following this resumption of operation, timer motor 28.1 continues its timed rotation for the-predetermined period which as previously mentioned may be two minutes. The cams remain in the position required to continue the extraction cycle and the tub and pump continue to remove liquid for the duration of this timed period. At the conclusion of this timed period, cams C1, C3, and C4 all restore opening the extraction circuits.

The timed controlled cycling then continues into the rinse fill and rinse operation in the previously described manner. At the conclusion of the rinse period the machine enters the rinse extraction period after which a repetition of the electrode shorting occurs providing variable length extraction. Following this variable length spin rinse period, the cycle concludes.

This embodiment could be used with minor circuit variations to provide an emergency shut-off mechanism in a circuit equipped as is FIG. 2. In this alternative arrangement, if the pressure switch were to fail, the electrodes would sense an overflow condition and shut off the water input, effectively ending the danger of the machine fiooding its environs.

The third embodiment employs the construction details shown in FIG. 6 and the circuit shown in FIG. 7, The embodiment of FIG. 6 employs a tilting water box 110 which is secured to casing 12 in pivotal fashion by hinge pin 111. The box is positioned outwardly of and adjacent to the water ejection holes 17 to catch water ejected therefrom. The box is biased by tension spring 112 to normally remain in substantially its horizontal position as shown in FIG. 6. A mercury switch 113 is afiixed to the box in any known manner so that it follows the motion of the box from the horizontal position to the tilted position indicated by the dotted lines in FIG. 6. With the box in the horizontal position, contacts 114 and 115 of the mercury switch complete a closed circuit path to the timer motor, and with the box in the tilted position these contacts open the circuit path.

The operation of the third embodiment may be described generally as follows: normally the water box is retained in the horizontal position by the action of the bias spring. Water is ejected from the tub and strikes the angled lid 118 and is deflected into the body proper of the box. When the weight of water received has increased sufficiently to overcome the bias of spring 112, the box tilts to the position shown by the dotted lines in FIG. 6. When the box tilts to this position, the mercury switch also tilts following the action of the box and opens the circuit through contacts 114 and 115. The

water in the box continually tends to drain out at a slow rate through drain hole 119 in the base of the box but as long as water flows into the box at a greater rate, the box remains tilted. When the level of water in the tub decreases, the amount of water flowing into the box diminishes, and as a result, the weight of water in the box is not sufiicient to overcome the bias of the spring 112 and the box restores to its horizontal position reclosing the mercury switch contacts 114 and 115.

The circuit of FIG. 7 is identical to that of FIG. 5 with the mercury switch contacts'replacing the contacts of relay 106, and thus this circuit does not require the electronic amplification circuit 100. It can be seen in FIG. 7 that contacts 114 and 115 complete a circuit for the operation of timer motor 28.1. These contacts will remain closed during the greater part of the operative cycle of the machine and consequently maintain timer motor 28.1 operative in its normal manner. This contact path is open only during the extraction period when liquid is being extracted from the tub in suflicient quantity to tip the water box and its attached mercury switch. Thus, the mercury switch contacts by opening, control the variable length extraction operations in the same manner as contacts R1 and R2 of the previously described second embodiment.

While I have shown and described particular embodiments of my invention, I do not desire the invention to be limited to the particular construction disclosed, and I intend by the appended claims to cover all modifications within the true spirit and scope of my invention.

What is claimed is:

l. A clothes washing machine, comprising a tub to receive liquid and clothes to be washed therein, means for rotating said tub to extract liquid from said tub and said clothes, mechanism for activating said extraction means to initiate rotation of said tub and subsequently to terminate said extraction operation, means including a timer motor to operate said extraction means activating mechanism to initiate said extraction operation and after a predetermined period of operation of said timer motor to terminate said extraction operation, and means responsive to a predetermined minimum rate of extraction of liquid to interrupt operation of said timer motor, circuit means for maintaining said tub rotative while the timer motor operation is interrupted, said interrupting means responsive to a substantial reduction in the rate of extraction of liquid to restore operation of said timer motor to complete its said period of operation.

2. A clothes washing machine, comprising a tub to receive liquid and clothes to be washed therein, means for rotatably mounting said tub, means for rotating said tub at a speed for centrifugal extraction of said liquid from said tub and said clothes, a chamber for receiving said liquid, switch means for controlling operation of said tub rotating means initiate and subsequently to terminate said extraction operation, means including a timer motor to operate said switch means to a first position to initiate said extraction operation and after a predetermined period of operation of said timer motor to operate said switch means to a second position terminating said operation, switch means for controlling operation of said timer motor, means responsive to a predetermined minimum accumulation of liquid in said chamber to actuate said timer motor controlling switch means from a first position effecting operation of said motor to a second position interrupting the operation thereof, and means operating continuously during said extraction operation for maintaining said tub rotative and for removing liquid from said chamber at a rate less than the rate of accumulation of liquid therein during the initial period of the extraction operation, whereby liquid will promptly accumulate beyond said predetermined minimum but subsequently will reduce to an amount insufficient to maintain said timer motor controlling switch means in its said second position, whereupon said timer motor controlling switch means will restore the timer motor to operation.

3. In a clothes washing machine comprising a tub to receive liquid and clothes to be washed therein, means for extracting liquid from said tub and said clothes, means for storing liquid extracted from said tub, means for expelling stored liquid, means for activating said extracting means and said expelling means simultaneously, means including a time controller operative to initiate said activating means, means responsive to a predetermined quantity of liquid having been stored for rendering said time control means inoperative and retaining said extracting means and said expelling means active thereafter, said liquid responsive means further responsive to less than said predetermined quantity of liquid remaining stored for rendering said time control means re-operative, said time control means thereafter de-activating said extracting means and said expelling means.

4. In a clothes washing machine comprising a tub to receive liquid and clothes to be washed and rinsed therein, means for extracting liquid from said tub and said clothes after a washing or rinsing operation, chamber means for storing liquid extracted from said tub, means for expelling stored liquid from said chamber, means for activating said extracting means and said expelling means simultaneously, means including a time controller operative to initiate said activating means, means responsive to more liquid having been extracted than expelled for rendering said time control means inoperative and retaining both said extracting means and said expelling means active thereafter, said liquid responsive means further responsive to a diminution of liquid being extracted from said tub for rendering said time control means reoperative, said time control means thereafter de-activating said extracting means and said expelling means after the passage of a predetermined length of time.

5. In a clothes washing machine comprising a tub to receive liquid and clothes to be washed therein, means for extracting liquid from said tub and said clothesysaid extracting means having a maximum extraction rate, means for storing liquid extracted from said tub, means for expelling stored liquid, said expelling means having a maximum expulsion rate less than the maximum rate of said extracting means, means for activating said extracting means and said expelling means simultaneously whereby said extracting means extracts initially at substantially its maximum rate and said expelling means expels liquid at substantially its maximum rate, means including a time controller operative to initiate said activating means, means responsive to storage of liquid from said tub at said extraction rate greater than the expulsion 7 rate for rendering said time control means inoperative and retaining said extracting means and said expelling means operative, said extracting means operative at substantially less than the maximum rate when substantially all of the liquid has been extracted from said tub, said liquid responsive means further responsive to the diminution of stored liquid resulting from said expulsion rate becoming substantially greater than the extracting rate to thereafter render said time control means re-operative, said time control means on re-operation de-activating said extracting means and said expelling means after the passage of a predetermined length of time.

6. In a clothes washing machine comprising a tub to receive liquid and clothes to be washed therein, time control means operative for conducting said machine through a cycle of operations including at least one liquid introducing operation, means for extracting liquid from said tub for subsequent removal from said machine, said time control means operative to render said extracting means operative, and circuit means positioned to be activated by liquid being extracted from said tub, said circuit means on activation rendering said time control means inoperative, said extracting means thereafter remaining operative to continue extracting liquid from said tub, said circuit means responsive to an absence of liquid being extracted for becoming inactive, said circuit means on 14 inactivation rendering said time control means operative to fontinue said conducting of the machine through its eye e.

7. In a machine as claimed in claim 6, said circuit means comprising a plurality of electrodes positioned to be short-circuited by liquid being extracted from said tub, and a control circuit including an operating path to said time control means, means in said control circuit responsrve to short-circuiting of said electrodes for opening said operating path and maintaining said path open as long as said electrodes remain short circuited.

8. In a machine as claimed in claim 6, a liquid retainmg member positioned to receive liquid extracted from said tub, means for biasing said member in a first positron, said circuit means comprising contactors in the operating path to said time control means; said contactors maintaining said path closed with said member in said first position, said retaining member on receipt of liquid being extracted pivotal to a second position, said contactors responsive to said receiving member pivoting to said second position for opening said path, and means in said retaining member for draining received liquid therefrom, said .bias means responsive to substantially an absence of liquid in said member for restoring said membe! to said first position, said contactors responsive to sald member restoring to said first position for re-closing the operating path to said time control means.

9. In a clothes washing machine having an outer liquid storage chamber and an inner imperforate tub, said inner tub adapted to receive liquid and clothes to be washed, timing means operative to conduct said machine through a cycle of operations including a tub filling operation and for initiating a liquid removal operation, means for centrifugally extracting liquid from said tub to said chamber during said liquid removal operation, a plurality of liquid e ection passages about the upper periphery of said tub eifecting said liquid extraction, contact means positioned on said chamber adjacent said passages and responsive to the fiow of liquid through said passages for interrupting a circuit path to said timing means and rendering said timing means inoperative, and circuit means for retaining said liquid extracting means operative with the timing means inoperative, said contact means responsive to the absence of liquid being extracted through said passages during said extraction cycle for retoring said timing means circuit path to render said timing means reoperative to continue the conducting of said machine through the remainder of said cycle of operations.

10. In a machine as claimed in claim 9, said contact means comprising a plurality of electrodes positioned to be short circuited during the fiow of liquid from said water e ection passages.

ll. In a machine as claimed in claim 9, a liquid receptlve structure having a liquid receiving opening adjacent said passages, means for biasing said structure in a first position, said structure responsive to liquid received therein for assuming a second position, said contact means comprising a mercury switch physically movable with said structure between a closed circuit condition in said first position and an open circuit condition in said second position.

12. In a clothes washing machine comprising a tub to receive liquid and clothes to be washed therein, control means for conducting said machine through a sequence of operations including a liquid fill operation, a washing operation and a liquid extraction operation, said control means comprising timing means for controlling said machine through said fill and said wash operations and to initiate said extraction operation, circuit means normally closed for maintaining said timing means in control of said operations, means responsive to the initiation of said extraction period for centrifugally extracting liquid from said tub, said extracting means extractive of liquid at a variable rate dependent on the amount of liquid in said tub, means responsive to the extraction of liquid at a rate corresponding to a large amount of liquid in said tub for opening said circuit means to interrupt the control of said timing means, extracting means circuit members eifective to maintain said extracting means continually extractive with said timing means control interrupted, said extraction responsive means further responsive to a rate of liquid being extracted corresponding to a small amount of liquid in said tub for closing said circuit means, said circuit means on re-closure restoring said timing means to control of said sequence of operations, said timing means being thereafter operative to render said extracting means control members ineffective and terminate said extraction operation.

13. A clothes washing machine, comprising a tub to receive liquid and clothes to be washed therein, mechanism for effecting the extraction of liquid from said tub, time-cycle means for initiating the operation of said mechanism and for maintaining said operation for a certain period of operation of said time-cycle means, an electric motor for operating said time-cycle means, a chamber for collecting liquid extracted from said tub, means for continuously removing liquid from said chamber, switch means in an energizing circuit for said timer motor, and means responsive to a predetermined accumulation of liquid in said chamber to actuate said switch means to interrupt the energizing circuit of said time cycle motor, means for maintaining the operation of said water-extraction mechanism during the period of inactivity of said time-cycle motor, said actuating means responsive to the removal of liquid from said chamber for actuating said switch means to restore operation of said timer motor to complete the said certain period of operation of said timer-cycle means, whereby the period of operation of said extraction mechanism comprises the sum of the active and inactive periods of said time-cycle motor.

14. The clothes washing machine according to claim 13, in which said switch means is operated to interrupt said time-cycle motor circuit in response to a predetermined load of liquid in said chamber.

15. The clothes washing machine according to claim 13, in which said switch means is operated to interrupt said time-cycle motor circuit in response to a predetermined weight of liquid in said chamber.

16. The clothes washing machine according to claim 13, in which said collection chamber is pivotally mounted for movement from a first position to a second position in response to a predetermined weight of liquid in said chamber and return to said first position upon a reduction in said weight of liquid, and said switch means is operated to its respective positions according to the position of said collection chamber.

17. In a clothes washing machine comprising a tub for receiving liquid and laundry to be washed therein, time control means operative to guide said machine through a cycle of operations including a wash operation and into an extraction operation, means for extracting liquid from said tub during said extraction operation, said extracting means activated by said time control means to start said liquid extraction, liquid receiving means positioned in the path of liquid being extracted from said tub, said liquid receiving means comprising a box structure for receiving and retaining extracted liquid, means for mounting said box structure eccentrically of the box structure center of gravity, means for normally biasing said structure to remainin a substantially horizontal position, a switch mechanism normally maintaining a closed circuit to said time control means, said structure eccentric mounting responsive to the receipt of a quantity of liquid extracted from said tub for gravitationally tilting movement against the effect of said biasing means to an oblique position, said switch mechanism responsive to said tilt motion for opening said closed circuit to said time control means whereby to place the duration of said extraction operation under the control of switch mechanism, means in said liquid receiving box structure for emitting liquid from said structure, said bias means responsive to a diminution of liquid remaining within said structure for returning said structure to said horizontal position, said switch mechanism responsive to said return for closing the circuit to said time control means to return the duration control to said time control means.

18. In a clothes washing machine comprising a tub for receiving liquid and laundry to be washed therein, time control means operative to guide said machine through a cycle of operations including a wash operation and into an extraction operation, means for extracting liquid from said tub during said extraction operation, said extracting means activated by said time control means to start said liquid extraction, liquid receiving means positioned in the path of liquid being extracted from said tub, said liquid receiving means comprising a box structure for receiving and retaining extracted liquid, means for mounting said box in an oil-center condition with respect to the center of gravity of the box structure,

means for normally biasing said box to remain in a substantially horizontal position, a switch mechanism mounted to said box, said switch mechanism responsive to said box remaining in said horizontal position for maintaining a closed circuit to said time control means, said box responsive to the receipt of a quantity of liquid extracted from said tub for gravitationally tilting against the efiect of said biasing means to' an oblique position, said switch mechanism responsive to said tilt motion for opening said closed circuit to said time control means whereby to place the duration of said extraction operation under the control of said switch mechanism, a drain aperture in said liquid receiving box to gravitationally emit liquid remaining in said box, said bias means responsive to a diminution of liquid remaining within said box for returning said box to said horizontal position, and said switch mechanism responsive to said return of said box for reclosing the circuit to said time control means to return the duration control to said time control means.

19. In a clothes washing machine comprising a tub to receive liquid and laundry to be washed therein, time control means for conducting said machine through a cycle of operations including a liquid introducing and washing operation, an outer chamber surrounding said tub, means operative to extract liquid from said tub for storage in said chamber, pump means operative to expel liquid from said chamber, said time control means operative at the conclusion of said washing operation for starting an extraction operation by rendering said extracitng and rendering said pump means operative, an extraction control device positioned in the path of liquid being extracted from said tub, said extraction control device comprising a pair of spaced electrodes positioned to be shorted by a flow of liquid being extracted from said tub, a circuit network controlled by the shorting of said electrodes for inactivating said time control means and for retaining said time control means inactive for the duration of extractive flow of liquid, a bleeder tube for feeding liquid being expelled from said pump means to said electrodes for aiding in maintaining said electrodes shorted out, said circuit network responsive to the cessation of extractive liquid fiow and cessation of flow through said bleeder tube resulting in opening of the short across said electrodes for re-activating said time control mean-s to continue the operations of said machine.

20. In a clothes washing machine comprising a tub to receive liquid and laundry to be washed therein, time control means for conducting said machine through a cycle of operations including a liquid introducing and washing operation, an outer chamber surrounding said tub, means operative to extract liquid from said tub for 17 storage in said chamber, pump means operative to expel liquid from said chamber, said time control means operative at the conclusion of said washing operation for rendering said extracting and rendering said pump means operative, an extraction control device positioned in the path of liquid being extracted from said tub, said extraction control device comprising a pair of spaced electrodes positioned to be shorted by a flow of liquid being extracted from said tub, a circuit network controlled by the shorting of said electrodes for inactivating said time control means and for retaining said time control means inactive for the duration of extractive flow of liquid, a bleeder tube for feeding liquid being expelled from said pump means to said electrodes for aiding in maintaining said electrodes shorted out, said circuit network including a slow acting relay to delay the restoration of and thereby to maintain said time control means inactive during short intervals between shorting of said electrodes, said circuit network responsive to the cessation of extractive liquid flow and cessation of flow through said bleeder tube resulting in opening of the short across said electrodes for releasing said relay and thereby re-activating said time control means to continue the operations of said machine.

21. In a clothes washing machine of the type in which clothes are washed in a quantity of liquid in a tub and the liquid in said tub and clothes is subsequently centrifugally extracted therefrom by rotation of said tub; the combination of a motor for rotating said tub to effect such extraction, an energizing circuit for said motor, a switch in said circuit, a motor-driven timing device for operating said switch to energize said tub motor circuit to initiate said extraction operation and to deenergize said motor circuit after a fixed time period of operation of said timing device which may be substantially less than that required to complete the extraction operation, means for energizing said timing device, means efiective subsequent to the commencement of said extraction operation but prior to the expiration of said fixed time period todisable said timing device and thereby maintain said extraction operation for a time not determined by said fixed time period, means for sensing the rate of extraction of liquid from said tub and clothing, and means responsive to a reduction in said extraction rate indicating that the desired centrifugal extraction is approaching completion to restore operation of said timing device for interruption of said tub motor circuit at the end of said fixed time period.

References Cited in the file of this patent UNITED STATES PATENTS 

